Manufacture of headers with nipples



May 9, 1961 A. P. J. HUET MANUFACTURE OF HEADERS wrm NIPPLES 2 Sheets-Sheet 2 Filed Oct. 26, 1956 FIG. 5

)IVENTOR ANDRE Pd. H05 7" FIG 4 .lll; I

Um'ed, State Pa 2,983,162 MANUFACTURE OF HEADERS wrrn NIPPLES Philippe Jean Huet, Paris, France, assignor to Combnstion' Engineering, Inc., New York, N.Y., a corporation of Delaware Filed Oct. 26, 1956,Ser. No. 618,616 Claims priority, application France Nov. 10, 1955 4 Claims. (C -1) This invention relates to the manufacture of nipples on headers.

It is known to provide tubulures or tube connections or nipples on a header by disposing inside the latter a punch operated by a hydraulic piston and the rising of which, in conjunction with a die applied to the outer face of the header, effects the formation of the nipple.

The nipples are generally provided on one and the same generatrix on the header and are sometimes fairly near one another. In these circumstances, it may be important to increase the strength of the metal along the generatrix where it is desired to form tubulures.

To this end, and in accordance with the present invention, the die, which is generally placed against the outer surface of the header for the purpose in conjunction with the punch of producing the nipple, is in two parts, and so designed as to encircle said header almost completely over a certain length. The region of the header corresponding to the generatrix to be worked having been previously brought to a suitable temperature, the halves of the die, which are so shaped as to efiect a centripetal compression of the header, are brought together to effect thickening of the wall of the header in the hot region of the generatrix to be worked, and if desired to form stitfen'ingribs in the metal in the region of said generatrix. In addition, the resulting increased thickness of metal in the region to be worked will enable taller tubulure lips to be obtained.

The preliminary operation of compression of the header by the half-dies may be eifected all along the header before the production proper of the nipples, or else immediately before the formation of the nipple or nipples by means of the punch or punches.

The following description when read with reference to the accompanying drawings, given by way of example, will enable the invention to be better understood. In the drawings:

Figure 1 is a cross-sectional view showing header to be worked, placed between the two half-dies of the apparatus embodyingthe inventiomf Fig'ure2 is a'view'sirn'ila'r to Figure 1, after the dies have been brought together, the nipple forming punch being disposed inside the header;

Figure 3 is a view similar to Figure 2, showing the punch raised and the nipple formed;

Figure 4 is a section of the header obtained.

As can be seen in the drawings, it is proposed to pro vide in a header a series of tubulures 40 (Figs. 3 and 4) along a generatrix projected at A. According to the invention, a die having two parts 12, 14 is disposed around the header, said parts being adapted to slide in the direction of the arrows F on a table 16, shown diagrammatically. The header 10 is supported at the bottom, in the vicinity of the generatrix B opposite to the generatrix A, by a fixed cradle-like base 18. Said base 18 has a recessed portion 20 of the height of the generatrix B in order to prevent the cooling of saidgeneratrix, which is heated,

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2 as will be explained hereinafter, and facilitates the deformation of the header when compression occurs, as will be stated hereinbelow.

The half-dies 12, 14 are so shaped that they can be applied to the outer surface of the header on both sides of the generatrices A and B. To be precise, the contour of the dies which are applied to the outer surface of the header is suchthat the portions 22, 24 of said dies are applied to the lower part of the header, on both sides of the generatrix B, while the portions 26, 28 are applied to the top part, on both sides of the generatrix A.

The wall of the header10 is first heated to the proper temperature, about 1000 0., all along the generatrix A. The opposite generatrix B is likewise heated to a certain temperature, preferably alower temperature, in such a manner as, on the one hand, to'compensate for the dilations of the header resulting from the unilateral heating of the generatrix A, and on the other hand to facilitate the obtaining, when the dies are brought together, of a resilient efiect of the two sides of the header comprised between the generatrices A and B, as will be explained hereinbelow. 1

When the dies 12, 14 are brought together in the direction of the arrows F, the portions 22, 24 and 26, 28 of the die surfaces are applied against the outer surface of the header in such a manner that on both sides of the heated generatrix B, forming a kind of hinge, the two sides of the header gripped between the portions 22, 24 of'the dies 12, 14 approach one another, with the effect that the header begins to become slightly oval in shape. On the other hand, the die portions 26, 28, which are applied on both sides of the generatrix A, cause squeezing of the metal in the directions 26 or 28, that is to say, in the direction of thickness of the wall of the header, with the result of causing a thickening of said wall in the region of the generatrix A.

As can be seen in Figure 2, the section of the header 10 in Figure 1 has been reproduced in broken lines as it was before the operation of bringing the dies together. After the operation of bringing the dies together, and in the position shown in Figure2, the portions 26, 28 of the dies 12, 14 have effected a slight flattening of the header and a compression of the metal on both sides of the generatrix A, with the result, as can be seen in Figure 2, that the wall in the region of the generatrix A has ac quired additional thickness.

The surfaces 26, 28 of the dies 12, 14 may moreover be so shapedthat, when compression takes place, transverse ribs 30 (Fig. 5) are formed in the header wall which have the effect of reinforcing said wall between the final nipples. 'Ihese ribs are obtained, for example, as a result of recesses of suitable'shape provided in the surface of the dies 12, '14, into which recesses the metal is pushed back whencompression occurs. On the other hand, as a result of squeezing the metal between the dies 12, 14; a longitudinal rib 32 may be formed on the header (Figure 4) by forcing the metal into a longitudinal groove provided between the dies 12, 14 (Figures 2 and 4) when they have been brought as close to one another as possible.

The half-dies 12, 14 and also the supporting base 18 are so designed that the surfaces of these members abutting against the header 10 during manufacture form part of detachable pieces mounted for example by dovetail joints on the dies and the base themselves. In this way it is possible to adapt the support surfaces to the dimensions of the header to be treated, by merely changing the detachable parts.

It then remains to produce the nipple, in known manner, by introducing into the interior of the header a jack 34 acting on a punch 36 which when raised, as seen weeds? in Figure 3, passes through the header wall, and by forcing the metal into a suitably shaped cavity 42 in the dies, forms the nipple 40.

r Thefact, however, that thedieis composed ;of;tW. part 1-2, 214 ;makes it possible :to provide iimrnediatelyabov each nipple an aperture 44 insaidvdie Figure .2). It is then possible to'introdnce through the aperture, correspondingto eachnippleaazrod which; :hearing against the headiof :the piston 36, .eauses the descent of the :latter once the .nipple has been formed, .sothat it :is unnecessary to employ a double-action hydraulic jack.

The :presence, moreover,of this aperturefl makes it possible topass a jet of hot gas, during the production of the nipple, over the metal which has been raised by the punch, .thus maintaining said metal at the desired high temperature and promoting the passage of the punch,

while .at the same time permitting the formation of a nipple h ving taller lip owing to the more malleable nature ;of the heated metal.

a The dies 12, 14 have a le corresponding at least to :the number of nipples prqducedin asingleoperation. 'Ihese-diescan be displaced along the header so as to permit all the nipples to be successively formed over the whole length of the header. But the header will-preferably be displaced in its axial direction between the fixed dies.

The operation of strengthening :the wall of the header along the generatrixto be treated can be carried out along the entire length of said generatrix before the nippics are formed. 0therw s he.hea er ca be given addion l h knes a h m w e t nipp a e being formed, the formation of'said nipples being then proceeded with immediately over the length of the header which has beencompressed. The latter method of procedure has the advant ge of not cgui ins m e t ane e heating-of the regions'of the header to be treated. a The fact of having obtained an increased'thicknesss of th metal of t head r wa the eg n of t s eratrix A, on the hand strengthens the, header in this r ion, a on t e o he ha p r it n pp es 4.0 to be o ta n d w th t e l ps sin mo meta i a aila e to form them.

What I claim is: V a

1; Apparatus for thickening the'wall of-a tubular header in locations where tubular nipples are to be produced comprising; a fixed base on-which the centralportion of the bottom of the header rests :to support the header; com- 7 plernentary die-halves adapted to be moved towards each other in a direction perpendicular to :the axis of the nipples to be created and formed with complementary parts of a recess for receiving the header with portions of the wall of said recess constituting working faces disposed to engage :the header at the upper part thereof at either side of the generatrix along which necks are to be formed, said work faces when the dies are moved together being located on radii less than that of the headerwhereby their engagement effects a displacement of the material in the header wall in directions toward the axis of the tubular neck to be formed so as to thicken the header wall.

2. Apparatus for the well .Q a t bu ar header where nipples are to be produced comprising a fixed base adapted to support the header, a die constituted of two parts which are applied against the header on both sides of the region to be worked and having working surfaces applied against the upper portiqn f the eade fe mi n .arad u vg ea e than ha of the header so as to effect "a lateral displacement of the wall metal while other purfaces engaging the lower and opposite portion of 'the header .areiso shaped as to effect compression of the header in a generally-circumferential direction in order to produce thickening of the wall of the header in the region in which it 'is' desired to form the nipples; 'recessed'portions being provided on the surfaces of the dies which compress the metal on both sides of the region to be worked,to constitute ribs on the surface of the header. 3. Apparatus for the fabrication of a series of nipples along a generatrix of a tubular header comprising: a punch located within the :header for forming a nipple in cooperation with a matrix applied to the exterior surface of the tube; said ,ma-trixcomprising two symmetrical halves with means formoving'ithem towards each other in a direction perpendiculari'to the plane of symmetry p s n h ou h t e s d se rat ix' f the tube; a half being provided :with a first face engageable during approaching movement .of the matrix halves with the upper portionQof the tube atopposite side of the said generatrix while the lower half of each matrix is provided with a second face engageable,duringzsaidmovement with portions of the tube at opposite sides of the generatrix which are situated diametrically opposite the first mentioned parts of the tube, said last working faces being ppl d a a ns the s bs q e t y .to the first me tioned surfaces .due totheir relativepositions with respect to said plane and cooperating therewith in such manner as to form a thickening of the upper wall of the tube whe e the n ppl i t be .f rmed y a p n means for supporting the tube during the said movement ofthe die halves.

4. An arrangement according to claim 3 characterized in t-hatrecesses are provided in the working faces engaging the upper-part ;of the tube so that when engagedwith the latter, circumferentialribs are formed on the surface of the header at the location of the nipple and a longitudinal rib is formed in the interval between two succcssive nipples.

Re erenc s C ed in he i e o h patent UNITED STATES PATENTS Netherlands Apr. 15, 1955 

